1. Field of Invention
The present invention relates to water treatment. More particularly, the present invention relates to growth inhibition of algae in water.
2. Description of Related Art
Many reservoirs around the world have water quality problems and one of the problems is nutrient pollution. Nutrient pollution comes from many sources, including fertilizer run off from farms, livestock waste and inadequately treated sewage. Excessive nutrients such as nitrogen and phosphorus contribute algae matter in our water supplies.
Algae blooms can have a significant environmental impact due to the decrease in oxygen in the water, resulting in the die-off of fish and other organisms. Moreover, when disinfectants, such as chlorine, are added to drinking water supplies, chlorine combines with some algae to form disinfection by-products, trihalomethane. Trihalomethanes and other disinfection by-products found in the tap water have been linked to cancer and birth defects. Furthermore, these algal blooms can produce significant quantities of natural toxins. Some algae, especially Cyanobacteria, produce either hepatotoxin or neurotoxin or even both. These toxins can cause severe dermatitis through skin contact, as well as gastrointestinal inflammation with oral exposure. Singly or in mixtures, these Cyanobacterial neurotoxins can cause death within minutes secondary to respiratory paralysis. At lower doses of hepatotoxin, enteritis and hepatitis are seen shortly after ingestion of these toxins.
In the conventional way, copper sulfate is probably the most widely used chemical application for controlling algae in water suppliers throughout the world. However, like other heavy-impact pollutants, copper accumulates in higher and higher concentrations as it moves up the food chain, and eventually leads to declines in fish and frog populations, according to several scientific studies. Short-term exposure to copper can lead to gastrointestinal distress, and long-term exposure causes liver or kidney damage. For the forgoing reasons, there is a need for inhibiting the growth of algae.